Engine Performance problem
1999 Chevy Lumina 6 cyl Front Wheel Drive Automatic 110000 miles
I paid $2300 for a used Chevy Lumina LS (the car, not the van) and weeks later I noticed the car has been losing power, going even slower than idle speed when I touch the gas pedal. In a minute or two, or if I pump the gas, the car begins to run normally. Shifting the car into overdrive for a few blocks seems to alleviate the problem faster.
I cannot replicate the problem, it just comes on randomly, at least twice a day. Usually it happens in the morning after I wake up from sleeping, but temperature does not seem to be relevant, on " cold" Vegas mornings, or on hot Vegas afternoons, the problem comes up again.
It seems like the engine is really struggling and running extremely rich. I calculated the gas mileage, and I only got 11 MPG, and that is talking about freeway speeds here in Las Vegas.
I pulled my car into a Autozone and after using a computer to scan my ECU for trouble codes, it pulled out a P1133 on my #1 cylinder for the O2 sensor " Insufficient Switching".
When I brake hard because of asshole drivers who are on their cell phones (and narrowly avoid a accident), the engine felt like it is stalling. When I touch the gas pedal again, it roughly goes back up to speed by jerking, then running normally.
Occasionally I can smell gasoline when I am driving.
I know the car is running really rich, but I do not want to invest $125 for a diagnostic by Chevrolet dealerships.
I am not sure if its really a bad O2 Sensor, or that it indicates a much more severe problem.
Should I pull my car into a dealership or just sell it? I want to know whether or not this is truly a complicated problem, or malfunctioning sensors or fuel injectors (I have used fuel injector cleaners, and iso-HEET when I thought there was water in my gas).